Vacuum forming as a method of molding a display is well known in the art. In order to vacuum form the display a mold is utilized with a heat-softened sheet of plastic. Typically, the mold is porous or includes holes in a forming surface, and a vacuum is applied which evacuates air from between the surface and the heat-softened plastic sheet to bring the sheet into conformance with the surface. In this manner the sheet takes the shape of the surface of the mold. The completed product is then removed from the mold.
Vacuum formed displays are generally integrally molded to include a top, side and bottom walls, with shelves extending horizontally there across. Vacuum forming is a reliable and cost effective method to create such types of displays. However, it is sometimes desirable to have additional elements formed in the display, for example, shelves having a front lip, and/or partitions extending from the front to the back of the shelf to define separate compartments within the shelf to house items. In the past, it has not been possible to vacuum form a display including shelves with features such as front lips and/or partitions, because the lips and partitions on the shelves make it impossible to remove the vacuum formed display from the mold due to the undercuts defined by the front lip and/or front to rear partitions. In some cases, where shelves having these features are required, the shelves are molded separately and then attached in some mechanical way to the display, which itself is integrally molded without any shelves. This results in a product which is more labor intensive, causing an increase in product cost, and also makes it more likely that difficulties will result when assembling the shelves.
Other methods of forming displays also exist, other than vacuum forming. For example, it is well known to form displays from cardboard blanks that are folded and manipulated which results in the display having a plurality of shelves. One such display is illustrated in U.S. Pat. No. 5,678,492 to Pinkstone et al. which discloses a display box with shelving formed from a single panel. In the '492 patent, a multi-tier display rack is formed from a flat, blank of sheet material including four panels which create a front, rear and opposed side walls of the display rack in the assembled position. In one embodiment, one panel includes sections which are partially punched out to form shelves of the display rack when assembled. Each shelf includes a slot therethrough. Another panel includes locking tabs which are partially punched out and pushed through the slots to lock the shelves in place. While generally effective, displays of this type lack the advantages of vacuum forming, namely, the ease of manufacture to produce multiple displays in a cost effective manner.
While a variety of methods for making displays including shelves exist today, there is continued need in the art for producing displays having shelves with partitions and/or lips, in a readily reproducible and cost effective manner.